1. Field of the Invention
The present invention relates to a top closing device for shaft furnaces, particularly blast furnaces, including an inlet hopper with inlet pipe, a rotating, vertically non-adjustable chute carrier with rotary drive, a pivotable chute in the furnace interior with external drive means, and sealing members between the rotating and stationary components.
2. Description of the Related Art
For filling and distributing the charges for charging shaft furnaces, devices have long been known which are constructed in accordance with the so-called McKee principal. In this construction, which is a gas seal bell, a small bell is arranged in the upper portion and a large bell is arranged in the lower portion. The upper of the bells or funnels arranged one above the other is rotatable.
An improvement of the McKee closing device is a conventional construction in which the lower large bell does not have to form a gas-tight closure because the rotary distributor closed by the bell is arranged in a tightly closed sleeve.
In another improvement according DE 36 32 724 C2, the problem of sealing between the lower distributor bell and the lower lock chamber is negligible because the upper funnel is constructed as a pressure-tight closeable lock chamber with the use of a stationary hood equipped with charging flaps.
DE OS 24 04 647 discloses a device for driving or moving a device for charging a blast furnace with raw materials, wherein a distribution channel is connected to the lower ends of an inner cylinder and an outer cylinder, wherein the inner cylinder and the outer cylinder are mounted so as to be rotatable together, are displaceable axially relative to each to each other and are supported independently of each other. The distribution channel is additionally rotatable together with the inner cylinder and the outer cylinder and is tiltable relative to the outer cylinder and the inner cylinder with the vertical movement of the inner cylinder or the outer cylinder.
The distribution channel interacts with drive means arranged at the outer side of the blast furnace, with an electric drive for the inner cylinder and with a hydraulic drive for lifting and lowering the outer cylinder.
The inner cylinder or the outer cylinder has a flange resting on a support means, wherein the outer cylinder or the inner cylinder is supported by a gear ring. A sealing means is provided between the inner cylinder and the outer cylinder.
DE-AS 10 13 681 discloses a sealing device at rotatable top closing devices of blast furnaces with a pressure ring fastened at the rotary hopper and a corresponding stationary annular sealing mass, wherein the sealing of pressure ring and sealing mass is effected by the force of a spring.
Readjustable springs are arranged in an annular housing fastened in a gas-tight manner on the upper bell, wherein the readjustable springs continuously press the annular sealing mass against the slip ring which rotates with the rotary hopper. The contact pressure of the springs is variably adjustable by means of a tightening device composed of a readjustable tightening screw.
In other known charging devices for blast furnaces in accordance with DE 20 35 458, DE 20 65 460, etc. which are operated with counterpressure at the opening, a stationary, central material inlet is provided through which the burden drops onto a rotatable chute. The rotary bearing and the drive components of the chute are located in the furnace space.
The charging device described last has also been improved in various ways. For example, the rotary bearing and drive components of the chute were arranged in their own housing which was separate from the remaining furnace space. The circulation gas inlet leads into this housing. The purpose of this is to prevent the hot and dust-containing blast furnace gases from entering.